White LED Backlight For Equipment

Edge-Lit
The most common type of LED Backlight for LCDs is edge-lit. Edge-lit Backlight refers to the use of LEDs around the perimeter of an LCD's screen. Edge-lit LCDs still feature the same liquid pixels as other LCDs. For the Backlight, though, they feature a perimeter or rim of many small LEDs. These LEDs will illimunate the LCD's pixels form the sides, thereby producing visible images.

Direct-Lit
Some LCDs feature direct-lit Backlight. Direct-lit Backlight is a type of LED-based Backlight that involves the use of LEDs in a grid pattern directly behind the pixel layer. It's not the same as edge-lit Backlight. With edge-lit Backlight, the LEDs are placed around the perimeter or rim of the LCD. With direct-lit Backlight, the LEDs are placed behind the pixel layer. They are arranged in columns of rows to form a grid. During operation, the grid of LEDs will illuminate the pixel layer from behind.

Local Dimming
Another common type of LED Backlight for LCDs is local dimming. With local dimming, clusters of multiple LEDs are individually controlled. Most local dimming LCDs feature a similar arrangement of LEDs as direct-lit LCDs. In other words, they have a grid of LEDs rather than a perimeter of LEDs. The difference is that local dimming LCDs can control groups or clusters of LEDs separately than the other LEDs.

Full Array Local Dimming
Finally, there's full array local dimming Backlight. This alternative Backlight technology is similar to direct lit Backlight. Both direct lit Backlight and full array local dimming Backlight feature a grid of LEDs. The same applies to local dimming as well. What is full array local dimming exactly? It's a Backlight technology in which each LED is individually controlled.
With direct-lit Backlight, all of the LEDs are controlled at once. With local dimming Backlight, clusters of LEDs can be controlled individually. And with full array dimming Backlight, each LED can be controlled individually. Fully array local dimming LCDs cost more than those using a different type of Backlight.

TheWhite LED Backlight for Equipment is the light source that provides the LCD panel. It is mainly composed of light source, light guide plate, optical film, plastic frame, etc. TheWhite LED Backlight for Equipment should have the characteristics of high brightness, long life, and uniform lighting. At present, there are three main types ofWhite LED Backlight for Equipments: EL, CCFL and LED. They are divided into edge-lit and direct-lit types according to the distribution position of the light source. As LCD modules continue to develop toward brighter, lighter, and thinner devices, edge-lit LEDWhite LED Backlight for Equipments for mobile phones have become the mainstream of mobile phoneWhite LED Backlight for Equipment development.

Since direct-type modules are thicker and do not conform to the trend of being light, thin and short, they are currently mostly side-lit. The function of the light guide plate is to guide the scattering direction of light to improve the brightness of the panel and ensure the uniformity of panel brightness. , the quality of the light guide plate has a great impact on theWhite LED Backlight for Equipment plate, which is one of the key technologies of the edge-litWhite LED Backlight for Equipment plate. The light guide plate uses the injection molding method to press acrylic into a plate with a smooth surface, and then uses a highly reflective and non-light-absorbing material to print diffusion dots on the bottom surface of the light guide plate by screen printing. The light source is located on the side of the light guide plate.

On the side, the light emitted is transmitted to the other end by reflection. When the light hits the diffusion point, the reflected light will spread to all angles, and then emit from the front of the light guide plate, using various density and different sizes of diffusion points. It can make the light guide plate shine evenly. The purpose of the reflective plate is to reflect the light exposed on the bottom back into the light guide plate to improve the efficiency of light use. Light guide plates can be divided into printed and non-printed types according to different process flows.

The printed type uses a material with high reflectivity and non-light absorption on an acrylic plate, and a round or square shape is printed on the bottom of the light guide plate by screen printing. diffusion point. The non-printing type uses precision molds to inject a small amount of granular materials with different refractive index into the acrylic material during injection molding of the light guide plate to directly form densely packed tiny bumps, which function like dots. At present, most domestic manufacturers still use printed light guide plates as light guide components.

Printed light guide plates have the advantages of low development cost and fast production, while non-printed light guide plates are more technically difficult, but have excellent performance in brightness. Mold development Technology is the bottleneck. In addition, according to the shape, it can be divided into flat panels and wedge-shaped boards. Flat panels are mostly used in monitors, and wedge-shaped boards are mostly used in notebook computers. As for the main purpose of the diffusion plate, it is to improve the brightness of the front of the product. It can make the light distribution more uniform so that the shadow of the reflection point cannot be seen from the front. In addition, since the directivity of the light after it is emitted from the diffuser plate is very poor, a prism sheet (optical film) must be used to correct the direction of the light to achieve the effect of condensing light and improve the brightness of the front.